Ýstanbul, Avcýlar ilçesi ambarlý heyelanýnýn gerilemesini önlemeye yönelik iksa sisteminin modellemesi

Afete Maruz Bölge, özetle; afet etüt raporlarýnda, olmuþ veya olmasý muhtemel afetlerden etkilendiði veya etkilenebileceði belirtilen, iyileþtirme çalýþmalarý ile teknik ya da ekonomik olarak ýslah edilmesi mümkün olmayan alanlar olarak tanýmlanabilir. Ancak, heyelanýn, bu tanýma göre belirlenen alan sýnýrýnda bulunan yerleþim yerlerine etkisi kimi zaman tartýþmadan uzak kalmaktadýr. Ýstanbul Avcýlar Ambarlý Heyelaný ve çevresi, bu tip bir alan olup, heyelan alaný 2005 yýlýnda Afete Maruz Bölge ilan edilmiþtir. Alanda, 56 adet yapý kullanýlmaz hale gelmiþ ve karar gereði alandaki tüm yapýlar yýkýlmýþtýr. Ancak, devam eden süreçte, alanda herhangi bir hareket izleme çalýþmasý yapýlmamýþtýr. Böylelikle, heyelanýn zaman içerisindeki durumu kontrolsüz býrakýlmýþ ve çevre yapýlarýn süreç içinde karþýlaþabilecekleri riskler deðerlendirilmemiþtir. Bu çalýþmada, Avcýlar Ambarlý Heyelaný alanýnýn, gerileyerek büyüme potansiyelinin ve mevcut durumda çevre yapýlardaki güvenlik koþullarýnýn ortaya konulmasý amaçlanmýþtýr. Alanda yapýlan önceki çalýþmalar deðerlendirilmiþ, çalýþma kapsamýnda yeni zemin araþtýrma sondajlarý ile indeks ve mekanik laboratuvar deneyleri yapýlmýþtýr. Sondajlarda 6 ay süreyle inklinometre ölçümü yapýlmýþ, kayma düzlemleri tespit edilmiþ ve aktif olarak hareketine devam ettiði belirlenen heyelanýn kayma hýzlarý hesaplanmýþtýr. Mevcut durum için, etki alanýndaki yapý yükleri de hesaba katýlarak yapýlan statik ve dinamik stabilite analizleri ile belirlenen risklere karþýn, konsol tip forekazýk sistemi modellenmiþ ve heyelanýn gerileyeceði alan için elde edilen güvenlik koþullarý tanýmlanmýþtýr.

Modeling of support system for preventing retrogressive slide of ambarlý landslide in Avcýlar district, Istanbul

Disaster-prone area is declared to were already affected or may be affected by the disasters that have been occurred or are likely to occur in the disaster survey reports. In addition, these areas should be areas that cannot be rehabilitation for technically or economically reasons by means of improvement studies. However, the future impact of the landslide on the settlements located at the boundary of the area determined according to this definition is sometimes not evaluated. Istanbul Avcýlar Ambarlý Landslide Area was declared a disaster-prone area in 2005. In the area, 56 buildings became unusable and all the buildings in the area were demolished due to resolution. However, during the ongoing process, any monitoring studies had not been working in the area. The landslide situation was left uncontrolled within this period, and risks to which the near structures might be affected were not evaluated. In this study, it is aimed to evaluate the potential of growth of The Landslide Area and the current security conditions in the near structures. Previous studies in the field were evaluated and new soil exploration drillings and index and mechanical laboratory experiments were performed within the scope of the study. Inclinometer measurements were made for 6 months, sliding planes were determined and moving velocities were calculated for the landslide that were determined to continue active movement. For the current situation, despite the risks determined by static and dynamic stability analyzes, taking into account the structural loads in the impact area, the cantilever type shoring system was modeled, and the safety conditions for the north of the area were defined.